The invention relates to improvements in apparatus for manipulating rod-shaped articles of the tobacco processing industry. More particularly, the invention relates to improvements in apparatus for changing the distance or spacing between sets (e.g., pairs) of coaxial rod-shaped articles including filter rod sections as well as plain or filter cigarettes, cigars, cheroots and cigarillos.
It is often necessary to transport rod-shaped articles of the tobacco processing industry (hereinafter called cigarettes for short) in the form of rows of parallel cigarettes wherein each cigarette of one row is coaxial with one cigarette of each other row. For example, a modern cigarette making machine of the type known as PROTOS is designed to deliver to a filter tipping machine two rows of parallel plain cigarettes wherein each cigarette of one row is coaxial with a cigarette of the other row and the coaxial cigarettes form pairs of closely or immediately adjacent cigarettes. The spacing between such pairs of coaxial cigarettes must be increased in the filter tipping machine in order to provide room for the introduction of a filter plug or filter rod section of double unit length. Each of the thus inserted filter plugs is then connected with the adjacent plain cigarettes by an adhesive-coated uniting band consisting of so-called tipping paper, and the thus obtained filter cigarettes of double unit length are severed midway between their ends (i.e., across the convoluted uniting bands and across the filter plugs) to yield pairs of filter cigarettes of unit length each having a plain cigarette, a filter plug of unit length, and one half of the respective convoluted uniting band.
Spreading of pairs of coaxial cigarettes is also necessary in certain makes of filter tipping machines. Thus, when successive filter cigarettes of double unit length are severed to yield pairs of filter cigarettes of unit length, it is often necessary to move the filter cigarettes of each pair axially and away from each other so that each of the thus separated filter cigarettes of unit length can be conveniently advanced to a discrete testing conveyor to undergo one or more tests including ascertaining the integrity of its wrapper, the permeability of its wrapper to atmospheric air, the condition of the seam, the resistance of the tobacco filler to the flow of tobacco smoke and/or other parameters which are important to the manufacturer and particularly to the consumer.
Published German patent application Serial No. 38 17 740 discloses an apparatus wherein the spreading unit which is used to increase the spacing between successive pairs of coaxial cigarettes or analogous rod-shaped articles of the tobacco processing industry employs two conical drums which taper in opposite directions. A drawback of such apparatus is that the conical drums occupy a substantial amount of space which is at a premium between a cigarette making machine and a filter tipping machine as well as in the interior of a filter tipping machine.